Biomechanical Analysis of CNS Gray Matter in Tension and Compression

Document Type : Research Article


1 S. Mehdizadeh is with the Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran (e-mail:

2 Corresponding Author, S. Najarian is with the Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran (e-mail:

3 F. Farmanzad is with the Department of Mechanical Engineering, Iran University of Science and Technology, Tehran, Iran (e-mail:

4 M. Khoshgoftar is with the Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran (e-mail:


The purpose of this study is to survey cross section changes of the animal brain samples during the tension and compression tests and comparison of the experimental results for three animals: bovine, sheep, and rabbit. A linear elastic theory with considering the necking in tension and barreling in compression has been considered for brain tissue. Bridgman method for tension and cross section updating method (using a picture analyzing through a computer program to trace cross section changes during the test) for compression has been applied in order to consider necking and barreling. It is shown that the effect of cross section changes of the samples during the test is not negligible. Differences in the behavior of brain tissue of bovine, sheep, and rabbit in both compression and tension are discussed. Results are in good agreement with previous works in the literature.


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